Laboratory Experiment Questions Please help!!?

Question

Can you please help me in my EE Theory Laboratory Subject?

These are the questions in our experiment.

**I AM USING ANALOG

1. In measuring the voltage, is it possible to use the 3-V range and 300-V range? Why? Explain.

2. Draw a linear scale with number calibrations 0,1,2,3 etc. through 10. Set off each major subdivision into 10 minor subdivisions. Show where 8.3 on the scale.

3. Which resistance is in the center of the ohm scale R x 1?

4. How is voltmeter connected in the circuit? (three resistors in series) if one of the resistors is to be measured (volts): Show the diagram.

5. How is ammeter connected in the circuit (three resistors in series) if the current is to be measured (amperes): Show the diagram.

6. What are the precautions to be taken in measuring voltage, current, and resistance?

Answer 1

A lot of these questions depend on information we don't have.

Look at your notes from the experiment.

Answer 2

1. It depends on what the expected measured voltage is. you would use a suitable voltage range. ie if the expected voltage was 0.3V you would use 3-V range at max and vice versa.

2. Can not answer as you havent stated what your trying to draw or show on the osciloscope.

3. I assume this relates to the scaling on a multimeter? the scaling increases in decades so your answer is likely to be around 5 * scaling range.

4. When measuring voltages across resistors, the voltmeter is placed in parallel to the resistor. Make sure you have the pos/neg around the right way or you get a negative value. cant show u a circuit diagarm

5. When measuring the current flowing through a resistor you need to put the ammeter in series with the resistor. specifically at the negative side of the resistor. again cant show a diagarm.

6. precautions; terminal polarity, voltage is measured in parallel, current is measured in series. multimeter settings, ie circuit wired correctly, and set to measure voltage or current or resistance. also make sure u do not hold the resistor as your body will affect your result.

Answer 3

What is the range of the voltage? 1.5 V or 220 V , is it A.C. or D.C.First of all if you are measuring e.g.10 volts and if you are at 3 volt range than you probably damage the meter.Always start with the largest range if you do not know anything about the circuit.About the scale you have 8 and 9 between them there are 9 lines like a ruler and like a cm with 10 mm scaling than isn't it clear that after 8 you have to count 3 lines ( 8 and the following 3 rd line( the line itself ) is 8,3. If you know the range and the type of the voltage in the middle of the multimeter there is selector switch, first select A.C. or D.C ,if you do not know start from A.C. Generally A.C. side is stated in red and the top value is 1000 Volts for both Voltages.For the multimeter there are 2 probes ( 1 is red the other is black )and on the meter there are 2 sockets ,one stated on it - com insert the short side ( sometimes it i male sometimes female )of the black probe in.The other one is  red + , insert the short side of the red probe in. The multimeter is on A.C on max range.Ä°f you are measuring voltage you have got 3 resistances, without touching any metal parts of the probes and circuit .Turn the power on for the circuit.Touch one of the probes to one side of the resistance and the other to the other side of the resistance.Make sure that you are touching properly.Ä°f the needle of the meter is on the left side of the scale than get the selector one step down (generally 250 )Ä°f yo have some reading try  to read it ( the scale starts with 0 ends with 10- 50-250. 0 is on the left side the scale is the lower 3 scales).you are on 250 on selector switch you read from 0 - 250 scale. if it is lower than 50 come one step down with the selector switch.than you use the 0-50 scale to read.On scale 0-10 there are small lines on the scale between two line is 0,2 Volt,on scale 0-50 scale every line is 1 volt, on scale 0-250 every line is 5 volts only thing you need to count down the lines coorrectly.This all about A.C. voltage measurement.It is almost the same thing with D.C but NOW THE PROBES ARE Ä°MPORTANT.You must check about D.C which side is +. If you make a mistake about the + side YOU MAY DAMAGE THE MULTÄ°METER.Ä°f you are using a battery in the circuit follow the wire starting from the + side of the battery until you come a resistance ( is there any other electrical components on the circuit I don't know but I assume there are just resistances.)This the + side you mus now touch the RED PROBE TO  + SÄ°DE OF THE RESÄ°STANCE and the balck probe to the other side of the resistance.If you follow it wrong the needle of the meter tries to go to the left side of the scale,this may damage the meters needle.Try to handle the second probe sensively to the resistance and watch the needle of the meter.The rest is the reading they are  the same scales and reading is same.These were all about VOLTAGE READÄ°NGS.When you are measuring the RESÄ°STANCE, turn the power of the circuit off.With the selector swich come to x 10 K the probes are not important touch one of the probes to one side of the resistance, and the other the other side of the resistance.Now the scale is the top scale.0 on the right side.If the needle stays on the left side,come one step down with the selector switch.( x K )if the needle comes to right side that you can read.than read it.from 0 - 2 every single line is 0,2 ohms, from 2 - 10 every single line is 0,5 ohms,from 10-20 every single line is 1 ohm,from 20 -50 every single line is 2 ohms,from 50-100 every single line is 5 ohms,from 100-200 every single line is 20 ohms and it goes like that ( for different meters the scalin may change you have to check it).What you have read on the scale you have to multiply it with 1000.The selector switch was on xK, if you can not read it on xK slection come one step down than probably you are at x 100 scale.Ä°f you can read it what you read must be multiplied by 100.Now lets come to ammeter ( ampermeter ).what we have done until now from the begining is paralel measurements.But now The AMMETER WÄ°LL BE CONNECTED TO THE CÄ°RCUÄ°T SERÄ°AL.What does this means?Turn of the energy of the circuit off.Take the wire out from the batteries + side if you have a seperate ammeter insert the probes in ,if the Circuit is D.C connect the + side of the battery to the red + probe and the other probe to the first resistance ( if there are no components between them.Than you have the ammeter connected.Ä°f you want to measure the curren which goes through 2 nd resistance take the ammeter out connect the ammeter + on the 1st resistance side and the other probe to the left side of the 2 nd resistance and than connect the battery.Do the same thing for the 3 rd resistance  but do not forget ALWAYS START WÄ°TH THE HÄ°GHEST selection range.The readings are all same as in voltage scale 0 on the left side ..... at the right side.It was too long for me but I hope You understand and solve how it is measured.DO NOT TOUCH ANY OPEN WÄ°RE OR CIRCUIT COMPONENT AND DO NOT TOUCH TOUCH OPEN PART OF THE PROBE ALWAYS HOLD  THE Ä°NSULATED SECTÄ°ON. WHEN YOU ARE FÄ°NÄ°SHED,OR AT EVERY STEP OF THE MEASUREMENT DO NOT FORGET TO SWÄ°CH OFF THE POWER.WHEN YOU ARE MEASURÄ°NG RESÄ°STANCE AND CONNECTING THE AMMETER MAKE SURE THAT POWER IS OFF.